Stainless steel elbow won’t produce corrosion, pitting, corrosion or wear and tear. Stainless steel or building one of the highest strength of metal materials in the material. Because the stainless steel has good corrosion resistance, so it can make structure parts permanently maintain the integrity of engineering design. Chromium stainless steel also has high mechanical strength and extensibility, easy processing and manufacturing of parts and can meet the needs of architects and structural designers. All metal and atmospheric oxygen in the reaction, formed in the surface oxide film. Unfortunately, in the ordinary carbon steel formed on the oxidation of iron oxide to continue, kept expanding rust, eventually forming holes. Can use paint or resistant to oxidation of the metal (for example, zinc, chromium and nickel) on plating to ensure that the surface of carbon steel, but, as we know, the protection is only a thin film. If the cover was damaged, the following steel began to rust.
Weak corrosive medium such as air, steam, water resistance and acid, alkali, salt and other chemical etching medium corrosion of the steel. Also called acid-proof stainless steel. In practical application, often called the weak corrosive medium corrosion resistant steel stainless steel, and called the resistance to chemical corrosion medium steel acid-resistant steel. Due to the chemical composition on the difference between the two, the former does not necessarily medium resistance to chemical corrosion, while the latter are generally not rust. The corrosion resistance of stainless steel depends on the alloy element content in the steel. Chromium is the basic element to stainless steel for corrosion resistance, while about 1.2% chromium content in steel, chromium and oxygen effect of corrosive medium, in the steel surface to form a thin layer of oxide film (since the passivation film), but to prevent further corrosion of steel substrate. Commonly used alloying elements except chromium and nickel, molybdenum, titanium, niobium, copper, nitrogen, etc., in order to meet the requirements of various applications on the microstructure and mechanical properties of stainless steel.
Stainless steel usually according to the matrix was divided into:
1, ferritic stainless steel. Chromium containing 12% ~ 30%. Its corrosion resistance, toughness and weldability with chromium content increases with the increase of chloride stress corrosion resistance is superior to other types of stainless steel.
2, austenitic stainless steel. Chromium is more than 18%, still contain about 8% of the nickel and small amounts of molybdenum, titanium, nitrogen and other elements. Good comprehensive performance, corrosion resistant to a variety of media.
3, austenitic, ferritic duplex stainless steel. The advantages of both austenitic and ferritic stainless steel, and has the superplasticity.
4, martensite stainless steel. High strength, but the plasticity and poor weldability.
The butt welding elbow calculation formula
The calculating formula of butt welding elbow:
1. The outer diameter X – wall thickness wall thickness X0.0387 X 1000 = 90 ° elbow bending radius present theoretical weight
For example: 426 x 90 ° 10 R = 1.5 D
(426-10) * 0.387 * 10 R600 present 1000 = 96.59 Kg
The 180 ° elbow on table 2 times, 45 ° calculated at 1/2;
2. – wall thickness (diameter) X thickness X0.02466 XR multiples X1.57 X = 90 ° bend the theoretical weight of nominal diameter
Example: for example: 426 x 90 ° 10 R = 1.5 D
(426-10 * 10 * 0.02466 * 1.5 * 1.57 * 400 D = 1.5 Kg
The 180 ° elbow on table 2 times, 45 ° calculated at 1/2.
Stamping welding elbow is to use the same as the pipe material of sheet in stamping die stamping into half a piece of ring elbow, then two and a half ring bend group for welding. Differ as a result of all kinds of pipe welding standard, usually by groups of some solid semi-finished products factory, site construction according to the welding pipe weld grade, therefore, also known as the butt welding elbow.
Source: Zhejiang Yaang Pipe Industry Co., Limited (www.yaang.com)